The present invention relates to a projection display apparatus that forms an optical image in accordance with an image signal, by means of an image display element and then projecting the thus formed optical image onto a screen or the like.
JP-A-2001-92011 discloses, in FIG. 2, a liquid crystal projector comprising a light source unit 1 composed of a reflector 10, a short circuiting arc discharge lamp 20 arranged in such a way that the direction of its arc is orthogonal to a horizontally extending optical axis L of the reflector 10, and a condenser lens 30 located on the optical axis L in front of the short circuiting arc discharge lamp 20, a support plate 31 for supporting the condenser lens 30, a front glass pane 40, a first optical integrator lens 41a, a second optical integrator lens 41b, a polarized beam splitter 42, a second condenser lens 43, a half wavelength phase difference plate 44, a first aluminum mirror 45a, a second aluminum mirror 45b, a third aluminum mirror 45c, a first dichroic mirror 46a, a second dichroic mirror 46b, a relay lens 47, a field lens 48, a liquid crystal display panel 49, a color synthesizing cross prism 50, a projection lens 51 and a screen 52.